Discovery Telescopes, Incorporated click here to see the Discovery DifferenceRECENT CUSTOMER COMMENTS: visit their website at: www.astrophoto.com "...words fail to describe the perfection of the primary mirror you made for us. I have NEVER seen anything like this before ...this mirror appears to be perfect! The inside-outside is so identical there is not the slighest clue which side of focus you are on. The Ronchi lines are so straight they look fake." "The action of the scope is excellent...very smooth motion... it is obvious that you have cut no corners in the construction." "I see now the other two (Discovery) 17.5" scopes that I looked through were no accident... your mirrors are the best I have ever seen... I don't know how you do it, but you have a severe talent for making extraordinay optics." "...stars appear as tiny, dazzling pinpoints of light...images like M13 take on a whole new appearance, and seeing the central star in the ring nebula with averted vision in a 17.5" mirror becomes routine. We cannot be more pleased with this telescope, and we have had many scopes over the years." WHY NOT PROVE IT TO YOURSELF WITH DISCOVERY'S EXCLUSIVE 60 DAY MONEY BACK GUARANTEE.

4. Telescopes Find an extensive alphabetical list of links to professional telescope information and observatory sites for astronomers. Observatory operates the AngloAustralian and UK Schmidt telescopes at Siding Spring, Australia, and a laboratory onhttp://www.cv.nrao.edu/fits/www/yp_telescope.html

Telescopes

1st High Energy Astrophysics Observatory

( HEAO 1. GSFC. NASA )

The first of NASA's three High Energy Astronomy Observatories, HEAO 1 was launched aboard an Atlas Centaur rocket on 12 August 1977 and operated until 9 January 1979. During that time, it scanned the X-ray sky almost three times over 0.2 keV - 10 MeV, provided nearly constant monitoring of X-ray sources near the ecliptic poles, as well as more detailed studies of a number of objects through pointed observations.

The second High Energy Astronomy Observatory (HEAO-B) was launched into an approximate 100-min low Earth orbit on 13 November 1978. Renamed the Einstein Observatory, it operated (with one significant interruption) until April 1981 and made over 5,000 targeted observations.

A Broad-Band Imaging X-ray All-Sky Survey ( ABRIXAS )

ABRIXAS is a small satellite mission which was planned to observe the X-ray sky in the energy band 0.5-10 keV. The mission failed shortly after launch in Spring 1999.

The Advanced Camera for Surveys (ACS) will be installed in the Hubble Space Telescope (HST) during a Space Shuttle mission scheduled in 2000. ACS will increase the discovery efficiency of the HST by a factor of ten. ACS will consist of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet at 1200 angstroms to the near infrared at 10,000 angstroms.

5. Isaac Newton Group Of Telescopes on the island of La Palma in The Canary Islands. Details about the facilities offered on the 4.2-m Category Science Astronomy International Facilities......The Isaac Newton Group of telescopes (ING) operates three worldclasstelescopes on La Palma, Canary Islands, Spain. The Isaac http://www.ing.iac.es/

w e i r d Telescopes A big West Virginia welcome to my weird telescope page. Achieving the very best views of the night sky is what this page is about. Showcased here are a variety of solutions by individuals in search of the perfect image. These instruments all seem strange: the need to use mirrors while keeping them from shadowing each other gives these telescopes odd geometries. Come join the quest. He appointed the moon for seasons: the sun knoweth his going down. Thou makest darkness and it is night: Anderson-Newtonian Carl Anderson's telescope resists easy classification. The primary is spherical but is too short to work as a Herschelian. Residuals of coma and astigmatism are removed by mechanically bending the primary using either of two schemes. A must see World's first binocular TCT At long last, the world now has a working tilted-component binocular. This achievement, a dream for many of us, was pulled off by John Francis. John has information about this newly completed telescope on his web site Brunn Telescope Austrian amateur, Guntram Lampert built this Brunn Telescope, the first tetra-schief named for its original designer.

8. The Telescope The telescope was one of the central instruments of what has been called the Scientific Revolution of the seventeenth century. But although Galilean telescopes of higher magnifications were certainly made, they were almost useless because of thehttp://es.rice.edu/ES/humsoc/Galileo/Things/telescope.html

The Telescope

The telescope was one of the central instruments of what has been called the Scientific Revolution of the seventeenth century. It revealed hitherto unsuspected phenomena in the heavens and had a profound influence on the controversy between followers of the traditional geocentric astronomy and cosmology and those who favored the heliocentric system of Copernicus. It was the first extension of one of man's senses, and demonstrated that ordinary observers could see things that the great Aristotle had not dreamed of. It therefore helped shift authority in the observation of nature from men to instruments. In short, it was the prototype of modern scientific instruments. But the telescope was not the invention of scientists; rather, it was the product of craftsmen. For that reason, much of its origin is inaccessible to us since craftsmen were by and large illiterate and therefore historically often invisible. Although the magnifying and diminishing properties of convex and concave transparent objects was known in Antiquity, lenses as we know them were introduced in the West at the end of the thirteenth century. Glass of reasonable quality had become relatively cheap and in the major glass-making centers of Venice and Florence techniques for grinding and polishing glass had reached a high state of development. Now one of the perennial problems faced by aging scholars could be solved. With age, the eye progressively loses its power to accommodate, that is to change its focus from faraway objects to nearby ones. This condition, known as

Large aperture Dobsonian telescopes for observers that want the best. Find out below why nothing else comes even close to an Obsession Telescope. We've tried to include most of our product information here on the Web, however you can still order the printed versions below to have and hold in your own hands! Infra-red photo of star guide and 18" Obsession at a public Star Walk at Copper Breaks State Park near Quanah, Texas. These public astronomy programs are held in cooperation with the Texas State Park system and feature half a dozen Obsession telescopes ranging in aperture from 15 to 30 inchs. Photo taken by Fred Koch. Klicken hier fur Deutschen, Declic ici pour les francais, Tecleo aqui para los espanoles, Scatto qui per italiano, Clique aqui para portugueses (WEBSITE TRANSLATIONS)

10. The BAIT Home Page Unattended astronomical telescopes with electronic cameras to search for supernovae and monitor the brightness of celestial objects.http://astro.berkeley.edu/~bait/

Welcome to the Official Web Site of the Unattended astronomical telescopes with electronic cameras to search for supernovae and monitor the brightness of celestial objects. Please visit our two facilities:

12. It Takes More Than One Kind Of Telescope To See The Light Educates readers on the different types of telescopes used and why diverse technologies are necessary for the advancement of space research. be solved by comparing images of different wavelengths, telescopes are only designed to detect a particular portion ofhttp://science.nasa.gov/newhome/headlines/features/ast20apr99_1.htm

It takes more than one kind of telescope to see the light

Why we need different types of telescopes to look at outer space

Feature Story: NASA NASA Science News presents "Feature Stories", where you can sit back, relax, and enjoy an in-depth look at ongoing research (or sometimes a story that's just plain fun). April 20, 1999 : By studying the electromagnetic emissions of objects such as stars, galaxies, and black holes, astronomers hope to come to a better understanding of the universe. Although many astronomical puzzles can only be solved by comparing images of different wavelengths, telescopes are only designed to detect a particular portion of the electromagnetic spectrum. Astronomers therefore often use images from several different telescopes to study celestial phenomena. Shown below is the Milky Way Galaxy as seen by radio, infrared, optical, X-ray and gamma-ray telescopes. The Multi-Wave Milky Way Galaxy radio infrared visual X-ray gamma ray Different types of telescopes usually don't take simultaneous readings. Space is a dynamic system, so an image taken at one time is not necessarily the precise equivalent of an image of the same phenomena taken at a later time. And often, there is barely enough time for one kind of telescope to observe extremely short-lived phenomena like gamma-ray bursts. By the time other telescopes point to the object, it has grown too faint to be detected.

Purchasing Amateur Telescopes

What you should know BEFORE you buy!

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18. Astronomical Optical Interferometry The use of multiple telescopes to produce high resolution images commonly used at most modern observatories. A literature review article.http://www.geocities.com/CapeCanaveral/2309/page1.html

Astronomical Optical Interferometry

A Literature Review by Bob Tubbs

St John's College Cambridge

April 1997 - updated 2002

Abstract This report documents the development of optical interferometry and provides a physical explanation of the processes involved. It is based upon scientific papers published over the last 150 years, and I have included references to the ones which are most relevant. The reader is assumed to have an understanding of modern optical theory up to undergraduate level - References 28 and 29 give explanations at a more basic level. The formation of images from interferometric measurements is discussed and several example images are included. Introduction Fizeau first suggested that optical interferometry might be used for the measurement of stellar diameters at the Academie des Sciences in 1867 . The short wavelength of light and the absence of sensitive calibrated detectors precluded more sophisticated interferometric measurements in the optical spectrum for over a century. After the Second World War most researchers instead turned to the radio spectrum, where macroscopic wavelengths and electronic detection greatly simplified the measurement of interferometric quantities. Modern computers, lasers, optical detectors and the data processing techniques developed for radio interferometry have recently enabled astronomers to produce high resolution images with optical arrays. At present only a few optical interferometer arrays are capable of image formation but many more are planned or under construction. The basic principles underlying the operation of optical interferometers have not changed, so I begin with a look at some of the earliest instruments.